Hydrolyzed proteins have been known for use as seasonings in the form of soya sauce, which traditionally has been prepared by enzymatic hydrolysis requiring a long period of time for preparation. In producing soya sauce, plant protein-containing materials and carbohydrates are inoculated with Aspergilli and the solid culture is fermented for 2 days to make koji, during this time enzymes are produced which are able to hydrolyze protein and carbohydrates in the moromi stage. The koji is mixed with a solution of common salt and water to give moromi, which is fermented for 4 weeks to 8 months by the activity of micro-organisms such as soya lactic acid bacteria and soya yeast, and the soya sauce is obtained by removing the solids portion from the fermented moromi.
A more rapid method of hydrolyzing proteins for producing seasonings was developed using hydrochloric acid in which the time required is only a few hours. However, the use of acid hydrolyzed plant protein (HPP) in culinary applications came under attack due to mono- and di-chloropropanols which were formed during the harsh processing conditions.
More recently, several processes were developed to replace HPP. Thus, in U.S. Pat. No. 5,523,100 a seasoning agent is prepared on modified standard soya sauce technology. In this process the koji is treated before forming the moromi, by a low hydrolysis temperature whereby the resultant seasoning has a stronger body than a standard soya sauce.
Biological plant protein hydrolysates which are used as neutral body givers in liquid seasonings, culinary applications and as bases for processed flavors like bouillons, soups and sauces, are also developed.
In U.S. Pat. No. 5,965,178, Baensch et al. disclose a process for the production of a seasoning which comprises preparing a fermented koji from protein-containing and carbohydrate materials and then hydrolyzing the koji material in the presence of a culture of lactic acid bacteria. The seasoning composition is obtained without preparing a moromi.
The problem is that biological hydrolysates are generally more expensive to produce than HPP due to lower yields, higher equipment costs and higher raw material prices e.g. enzymes (commercial or own production by fermentation).
Finally, it is also known to hydrolyze wheat gluten enzymatically using commercially available enzymes. The critical points in the development of WGH-te (Wheat Gluten Hydrolysate—technical enzymes) processes are mainly the high costs of these enzymes, separation of solids from the hydrolysates with high yield and microbiological protection of the hydrolysates since they are run without or low salt concentrations, at temperatures permissible for certain spoilage micro-organisms.
The present invention aims to provide a natural and “soft technology” procedure to prepare seasonings, which is very much desired by consumers these days.